<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>控制文本中的字母大小写</title>
</head>

<body>
    <style>
        p.uppercase {
            text-transform: uppercase;
        }

        p.lowercase {
            text-transform: lowercase;
        }

        p.capitalize {
            text-transform: capitalize;
        }
    </style>
    <p class="uppercase">This is some text.</p>
    <p class="lowercase">This is some text.</p>
    <p class="capitalize">This is some text.</p>
</body>

</html>